Braking Distance of Cycles

On Sun, 15 Aug 2010 18:38:27 +0100, JMS garbled:

On Sun, 15 Aug 2010 18:17:18 +0100, Clive George
wrote:

snip


(I've not seen JMS asking this question before. Anybody got message
ids?)

Hello it's nut-job George

That's ****ing rich, coming from you.

Too subtle by half sunshine.

Why not accuse me of lying?

You're a ****ing lying nut-job.

Happy now?

--

Mike P

On Aug 16, 9:17*am, Mike P wrote:

[ob. JMS]

You're a ****ing lying nut-job.

http://groups.google.com/groups/sear...s_uauthors=JMS

One hit.

Substitute "judith" for "JMS" and you get one hit but not asking that
question.

Looks like you're right, or perhaps JMS "keeps asking" the voices in
her head? Anyway, Google finds no evidence that the question has been
asked by the OP more than very occasionally at most.
--
Guy

On 16/08/2010 09:04, Mike Causer wrote:
On Mon, 16 Aug 2010 06:02:57 +0000 (UTC)
Ian wrote:

It would stop even better if it had disc brakes.

Only if there's something wrong with your current side-pulls,
centre-pulls, vee-brakes or cantis. Discs would be better than
back-pedal hub brakes though.

Why?

The only back-pedal hub-brake in my bikes locks the back wheel very
easily. Are you suggesting discs will somehow allow you to brake more
than a locked rear wheel?

The limiting factor for dry or mildly wet (but not greasy or icy) roads
is the back wheel lifting off the ground.

Does that not rather contradict your comments about back-pedal
brakes?

How well does the back brake work when the wheel is off the ground?


In fact the maximum retardation you can get from the back brake alone
regardless of type is about 0.33 G on a high-friction surface. "Discs" does
imply a brake at the front too, but a rear disc used on its own will have the
same limit as the hub brake. The only back-pedal brake on any of my bikes
won't lock the wheel though.

Aww. The best bit about back-pedal brakes is being able to pull broadies
with them - they're great for that, and if they can't lock the wheel you
can't :-(

On Mon, 16 Aug 2010 09:04:15 +0100, Mike Causer wrote:
On Mon, 16 Aug 2010 06:02:57 +0000 (UTC)
Ian Smith wrote:

It would stop even better if it had disc brakes.

Only if there's something wrong with your current side-pulls,
centre-pulls, vee-brakes or cantis. Discs would be better than
back-pedal hub brakes though.

Why?

The only back-pedal hub-brake in my bikes locks the back wheel very
easily. Are you suggesting discs will somehow allow you to brake more
than a locked rear wheel?

The limiting factor for dry or mildly wet (but not greasy or icy) roads
is the back wheel lifting off the ground.

Does that not rather contradict your comments about back-pedal
brakes?

How well does the back brake work when the wheel is off the ground?

Exactly, so why do YOU say that a back-pedal brake equipped bike will
brake less well?

You say that a disk-equipped bike will stop better than a back-pedal
brake equipped bike. I can only conclude that you think disk-braked
wheels do provide retardation when they are off the ground. That's
why I asked why you think back-pedal-braked bikes stop less well than
disk-braked bikes.

regards, Ian SMith
--
|\ /| no .sig
|o o|
|/ \|

In message 20100816090415.3202e278@surya, Mike Causer
writes
On Mon, 16 Aug 2010 06:02:57 +0000 (UTC)
Ian Smith wrote:

It would stop even better if it had disc brakes.

Only if there's something wrong with your current side-pulls,
centre-pulls, vee-brakes or cantis. Discs would be better than
back-pedal hub brakes though.

Why?

The only back-pedal hub-brake in my bikes locks the back wheel very
easily. Are you suggesting discs will somehow allow you to brake more
than a locked rear wheel?

The limiting factor for dry or mildly wet (but not greasy or icy) roads
is the back wheel lifting off the ground.

Does that not rather contradict your comments about back-pedal
brakes?

How well does the back brake work when the wheel is off the ground?


In fact the maximum retardation you can get from the back brake alone
regardless of type is about 0.33 G on a high-friction surface. "Discs" does
imply a brake at the front too, but a rear disc used on its own will have the
same limit as the hub brake. The only back-pedal brake on any of my bikes
won't lock the wheel though.

The sachs coaster on my old rear hub could easilt lock the rear wheel.
--
Chris French

In message , Ian Smith
writes
On Mon, 16 Aug 2010 09:04:15 +0100, Mike Causer
wrote:
On Mon, 16 Aug 2010 06:02:57 +0000 (UTC)
Ian Smith wrote:

It would stop even better if it had disc brakes.

Only if there's something wrong with your current side-pulls,
centre-pulls, vee-brakes or cantis. Discs would be better than
back-pedal hub brakes though.

Why?

The only back-pedal hub-brake in my bikes locks the back wheel very
easily. Are you suggesting discs will somehow allow you to brake more
than a locked rear wheel?

The limiting factor for dry or mildly wet (but not greasy or icy) roads
is the back wheel lifting off the ground.

Does that not rather contradict your comments about back-pedal
brakes?

How well does the back brake work when the wheel is off the ground?

Exactly, so why do YOU say that a back-pedal brake equipped bike will
brake less well?


It appears that mike has a particularly badly performing back-pedal
brake as it won't lock his back wheel.
--
Chris French

On Sun, 15 Aug 2010 20:12:53 +0000 (UTC), Mike P wrote:

snip

Thanks

Is it neccessary to read it to be a safe rider, if one is already in
possesion of common sense? - a serious question..

So we have the following stopping distances:


Car - 20 mph dry 12 metres
Cycle : 17 metres

Car : 20mph wet 14 metres
Cycle : 41 metres


Car : 25 dry 17 metres
Cycle : 24 metres

Car : 25 wet 20 metres
Cycle : 57 metres

No wonder Porky Chapman was reluctant to answer the question elsewhere

It has been argued that there is no need for cycles to be covered by
speed limits such as 10mph 20mph 30mph 40mph.

I have said that cyclists are more likely to be involved in an
accident at any speed cf a car as they cannot stop in the same
distance, in the rain the cyclists cannot see as well as a car driver,
the cycle is not as stable, nor is it as manoeuvrable.

It is now very clear that they *cannot* stop as quickly as a car in
the same circumstances.

This reinforces the need for cyclists to be covered by the speed
limits - particularly where there is a good chance they will exceed
them.


I agree that if one applies common sense then one would not ride too
fast.

Have you seen the high speed at which some cyclists ride - either on
the road or on the pavement?

There is no common sense there.
--
Latest accident figures from DfT Q1 2010
Killed or Seriously Injured:

Pedestrians DOWN 8%
Car Users DOWN 8%
Motorcycle users DOWN 8%
Cyclists UP : 4%

Spot a theme?

On Mon, 16 Aug 2010 08:17:27 +0000 (UTC), Mike P
wrote:

snip



Happy now?

--
Many thanks for your continued keen interest in my posts.
However, it is a pity that you never actually contribute anything.
If you just ask - I will send you the monthly digest of them - just in case you have missed one.

On Mon, 16 Aug 2010 13:21:41 +0100, JMS garbled:

On Mon, 16 Aug 2010 08:17:27 +0000 (UTC), Mike P
wrote:

snip



Happy now?

--
Many thanks for your continued keen interest in my posts. However, it is
a pity that you never actually contribute anything.

You're just an irritation to all the users of this group, and the others
which you infest. You've *never* contributed *anything* to *any* of them
other than to **** people off.


--

Mike P

"Mike P" wrote in message
...
On Mon, 16 Aug 2010 13:21:41 +0100, JMS garbled:

On Mon, 16 Aug 2010 08:17:27 +0000 (UTC), Mike P
wrote:

snip



Happy now?

--
Many thanks for your continued keen interest in my posts. However, it is
a pity that you never actually contribute anything.

You're just an irritation to all the users of this group, and the others
which you infest. You've *never* contributed *anything* to *any* of them
other than to **** people off.

I could say the same about you Mike. If you don't want to read what Judith
writes, use your killfile. I have several entries in mine which makes using
usenet more enjoyable.